Ultra-high pressure food processing is referred to after placing food in a container, then placing the container in an ultra-high pressure food processing chamber, filling up the chamber with liquid usually with water continuously to make the pressure inside the chamber reach above 100 MPa, usually 6000 atmosphere pressure, to kill the bacteria in the food. The material container disclosed in the prior art is a simple frame, which can not utilize the most of its inner space for placing food, and the process of placing food is time consuming, labor intensive, and not suitable for in-line operation. In addition, the material container disclosed in the prior art bears low pressure only and it is likely to be damaged.